152
FZUS51 KBOX 200505
CWFBOX
COASTAL WATERS FORECAST FOR MASSACHUSETTS AND RHODE ISLAND
NATIONAL WEATHER SERVICE BOSTON/NORTON MA
104 AM EDT MON APR 20 2026
COASTAL WATERS FROM THE MERRIMACK RIVER MA TO WATCH HILL RI OUT
TO 25 NM
ANZ200-201800-
104 AM EDT MON APR 20 2026
SYNOPSIS FOR MASSACHUSETTS AND RHODE ISLAND COASTAL WATERS
A COLD FRONT MOVES OVER THE COASTAL WATERS THIS AFTERNOON WITH A
PERIOD OF GUSTY WEST/NORTHWEST WINDS WITH GUSTS UP TO 30 KNOTS. HIGH
PRESSURE BUILDS OVER THE WATERS EARLY THIS WEEK SUPPORTING
RELATIVELY CALM CONDITIONS WITH SEAS LESS THAN 4 FEET AND WINDS
GENERALLY 10 KNOTS OR LESS SUSTAINED.
ANZ250-201800-
COASTAL WATERS EAST OF IPSWICH BAY AND THE STELLWAGEN BANK
NATIONAL MARINE SANCTUARY-
104 AM EDT MON APR 20 2026
REST OF TONIGHT
W WINDS 10 TO 15 KT WITH GUSTS UP TO 20 KT.
SEAS 3 TO 5 FT. WAVE DETAIL: NW 3 FT AT 4 SECONDS AND SE 3 FT AT
7 SECONDS.
MON
W WINDS 5 TO 10 KT, BECOMING SW IN THE AFTERNOON. SEAS
2 TO 4 FT. WAVE DETAIL: SE 3 FT AT 7 SECONDS AND W 2 FT AT
4 SECONDS.
MON NIGHT
N WINDS 5 TO 10 KT, INCREASING TO 15 TO 20 KT AFTER
MIDNIGHT. SEAS 2 TO 4 FT. WAVE DETAIL: NE 4 FT AT 8 SECONDS AND
NW 3 FT AT 4 SECONDS.
TUE
N WINDS 10 TO 15 KT WITH GUSTS UP TO 20 KT, BECOMING NE
5 TO 10 KT IN THE AFTERNOON. SEAS 2 TO 4 FT. WAVE DETAIL: N 4 FT
AT 5 SECONDS AND SE 1 FOOT AT 7 SECONDS.
TUE NIGHT THROUGH WED NIGHT
SW WINDS 10 TO 15 KT. SEAS 2 TO
3 FT. WAVE DETAIL: E 3 FT AT 9 SECONDS AND SE 3 FT AT 16 SECONDS.
THU THROUGH FRI NIGHT
NE WINDS 5 TO 10 KT. SEAS 2 TO 3 FT.
WAVE DETAIL: S 3 FT AT 7 SECONDS AND E 3 FT AT 9 SECONDS.
SEAS ARE REPORTED AS SIGNIFICANT WAVE HEIGHT, WHICH IS THE
AVERAGE OF THE HIGHEST THIRD OF THE WAVES. INDIVIDUAL WAVE
HEIGHTS MAY BE MORE THAN TWICE THE SIGNIFICANT WAVE HEIGHT.
ANZ251-201800-
MASSACHUSETTS BAY AND IPSWICH BAY-
104 AM EDT MON APR 20 2026
REST OF TONIGHT
W WINDS 10 TO 15 KT WITH GUSTS UP TO 20 KT.
SEAS 2 TO 3 FT. WAVE DETAIL: SE 3 FT AT 7 SECONDS AND NW 2 FT AT
3 SECONDS.
MON
W WINDS 5 TO 10 KT. SEAS 2 TO 3 FT. WAVE DETAIL: W 2 FT AT
3 SECONDS AND SE 2 FT AT 7 SECONDS.
MON NIGHT
N WINDS 10 TO 15 KT, INCREASING TO 15 TO 20 KT AFTER
MIDNIGHT. SEAS 2 TO 3 FT. WAVE DETAIL: N 3 FT AT 6 SECONDS AND NW
2 FT AT 3 SECONDS.
TUE
N WINDS 10 TO 15 KT WITH GUSTS UP TO 20 KT, BECOMING E
5 TO 10 KT IN THE AFTERNOON. SEAS 2 TO 3 FT. WAVE DETAIL: N 3 FT
AT 5 SECONDS AND SE 1 FOOT AT 7 SECONDS.
TUE NIGHT AND WED
S WINDS 10 TO 15 KT. SEAS AROUND 2 FT. WAVE
DETAIL: W 2 FT AT 2 SECONDS AND SE 2 FT AT 3 SECONDS.
WED NIGHT
S WINDS AROUND 10 KT, BECOMING SW AFTER MIDNIGHT.
SEAS AROUND 2 FT. WAVE DETAIL: S 2 FT AT 4 SECONDS AND E 2 FT AT
9 SECONDS.
THU THROUGH FRI NIGHT
NE WINDS 5 TO 10 KT. SEAS 2 TO 3 FT.
SEAS ARE REPORTED AS SIGNIFICANT WAVE HEIGHT, WHICH IS THE
AVERAGE OF THE HIGHEST THIRD OF THE WAVES. INDIVIDUAL WAVE
HEIGHTS MAY BE MORE THAN TWICE THE SIGNIFICANT WAVE HEIGHT.
ANZ231-201800-
CAPE COD BAY-
104 AM EDT MON APR 20 2026
REST OF TONIGHT
W WINDS 10 TO 15 KT WITH GUSTS UP TO 20 KT.
SEAS 2 TO 3 FT. WAVE DETAIL: NW 2 FT AT 4 SECONDS AND S 2 FT AT
6 SECONDS.
MON
W WINDS 5 TO 10 KT. SEAS AROUND 2 FT. WAVE DETAIL: NE 2 FT
AT 7 SECONDS AND NW 1 FOOT AT 4 SECONDS.
MON NIGHT
N WINDS 5 TO 10 KT, INCREASING TO 10 TO 15 KT WITH
GUSTS UP TO 20 KT AFTER MIDNIGHT. SEAS AROUND 2 FT. WAVE DETAIL:
N 2 FT AT 5 SECONDS AND SE 1 FOOT AT 7 SECONDS.
TUE
N WINDS 10 TO 15 KT WITH GUSTS UP TO 20 KT, BECOMING NE
5 TO 10 KT IN THE AFTERNOON. SEAS AROUND 2 FT. WAVE DETAIL: N
2 FT AT 4 SECONDS AND S 1 FOOT AT 7 SECONDS.
TUE NIGHT THROUGH WED NIGHT
SW WINDS 10 TO 15 KT. SEAS AROUND
2 FT. WAVE DETAIL: SW 2 FT AT 4 SECONDS AND NE 2 FT AT 5 SECONDS.
THU THROUGH FRI NIGHT
NE WINDS 5 TO 10 KT. SEAS AROUND 2 FT.
WAVE DETAIL: NW 1 FOOT AT 2 SECONDS AND E 1 FOOT AT 9 SECONDS.
SEAS ARE REPORTED AS SIGNIFICANT WAVE HEIGHT, WHICH IS THE
AVERAGE OF THE HIGHEST THIRD OF THE WAVES. INDIVIDUAL WAVE
HEIGHTS MAY BE MORE THAN TWICE THE SIGNIFICANT WAVE HEIGHT.
ANZ254-201800-
COASTAL WATERS FROM PROVINCETOWN MA TO CHATHAM MA TO NANTUCKET MA
OUT 20 NM-
104 AM EDT MON APR 20 2026
REST OF TONIGHT
NW WINDS 10 TO 15 KT WITH GUSTS UP TO 20 KT.
SEAS 3 TO 5 FT. WAVE DETAIL: NW 3 FT AT 4 SECONDS AND SE 3 FT AT
7 SECONDS.
MON
W WINDS 5 TO 10 KT, BECOMING SW IN THE AFTERNOON. SEAS
2 TO 4 FT. WAVE DETAIL: NW 2 FT AT 5 SECONDS AND SE 2 FT AT
7 SECONDS.
MON NIGHT
NW WINDS 5 TO 10 KT, BECOMING N 10 TO 15 KT WITH
GUSTS UP TO 20 KT AFTER MIDNIGHT. SEAS 2 TO 3 FT. WAVE DETAIL: NE
3 FT AT 7 SECONDS AND S 2 FT AT 7 SECONDS.
TUE
N WINDS 10 TO 15 KT WITH GUSTS UP TO 20 KT, BECOMING NE
5 TO 10 KT IN THE AFTERNOON. SEAS 2 TO 4 FT. WAVE DETAIL: N 3 FT
AT 5 SECONDS AND S 1 FOOT AT 7 SECONDS.
TUE NIGHT AND WED
S WINDS 10 TO 15 KT. SEAS 2 TO 3 FT. WAVE
DETAIL: N 3 FT AT 6 SECONDS AND SW 2 FT AT 3 SECONDS.
WED NIGHT
S WINDS AROUND 10 KT, BECOMING SE AFTER MIDNIGHT.
SEAS 2 TO 3 FT. WAVE DETAIL: E 3 FT AT 10 SECONDS AND SW 2 FT AT
4 SECONDS.
THU THROUGH FRI NIGHT
NE WINDS 5 TO 10 KT. SEAS 2 TO 3 FT.
SEAS ARE REPORTED AS SIGNIFICANT WAVE HEIGHT, WHICH IS THE
AVERAGE OF THE HIGHEST THIRD OF THE WAVES. INDIVIDUAL WAVE
HEIGHTS MAY BE MORE THAN TWICE THE SIGNIFICANT WAVE HEIGHT.
ANZ255-201800-
COASTAL WATERS EXTENDING OUT TO 25 NM SOUTH OF MARTHAS VINEYARD
AND NANTUCKET-
104 AM EDT MON APR 20 2026
REST OF TONIGHT
NW WINDS 15 TO 20 KT. SEAS 3 TO 5 FT. WAVE
DETAIL: W 4 FT AT 6 SECONDS AND SE 2 FT AT 7 SECONDS.
MON
W WINDS 5 TO 10 KT, BECOMING SW IN THE AFTERNOON. SEAS
2 TO 4 FT. WAVE DETAIL: SW 3 FT AT 7 SECONDS AND E 2 FT AT
7 SECONDS.
MON NIGHT
NW WINDS 5 TO 10 KT, BECOMING N 15 TO 20 KT AFTER
MIDNIGHT. SEAS 2 TO 3 FT. WAVE DETAIL: NW 2 FT AT 4 SECONDS AND
SW 2 FT AT 7 SECONDS.
TUE
N WINDS 15 TO 20 KT, BECOMING NE 5 TO 10 KT IN THE
AFTERNOON. SEAS 2 TO 4 FT. WAVE DETAIL: N 3 FT AT 5 SECONDS AND S
1 FOOT AT 6 SECONDS.
TUE NIGHT
S WINDS 5 TO 10 KT, BECOMING SW 10 TO 15 KT AFTER
MIDNIGHT. SEAS 2 TO 3 FT. WAVE DETAIL: SW 2 FT AT 3 SECONDS AND E
2 FT AT 6 SECONDS.
WED
S WINDS 10 TO 15 KT. GUSTS UP TO 20 KT IN THE AFTERNOON.
SEAS 2 TO 4 FT. WAVE DETAIL: SW 3 FT AT 5 SECONDS AND E 3 FT AT
9 SECONDS. A CHANCE OF SHOWERS IN THE MORNING.
WED NIGHT
SE WINDS AROUND 10 KT, BECOMING NE AFTER MIDNIGHT.
SEAS 3 TO 4 FT.
THU THROUGH FRI NIGHT
NE WINDS 10 TO 15 KT. SEAS 2 TO 4 FT.
SEAS ARE REPORTED AS SIGNIFICANT WAVE HEIGHT, WHICH IS THE
AVERAGE OF THE HIGHEST THIRD OF THE WAVES. INDIVIDUAL WAVE
HEIGHTS MAY BE MORE THAN TWICE THE SIGNIFICANT WAVE HEIGHT.
ANZ256-201800-
COASTAL WATERS FROM MONTAUK NY TO MARTHAS VINEYARD EXTENDING OUT
TO 20 NM SOUTH OF BLOCK ISLAND-
104 AM EDT MON APR 20 2026
REST OF TONIGHT
NW WINDS 15 TO 20 KT. SEAS 3 TO 5 FT. WAVE
DETAIL: NW 3 FT AT 5 SECONDS AND SW 3 FT AT 6 SECONDS.
MON
W WINDS 5 TO 10 KT. SEAS 2 TO 3 FT. WAVE DETAIL: NW 2 FT
AT 4 SECONDS AND SW 2 FT AT 6 SECONDS.
MON NIGHT
NW WINDS 10 TO 15 KT, BECOMING N 15 TO 20 KT AFTER
MIDNIGHT. SEAS 2 TO 4 FT. WAVE DETAIL: NW 3 FT AT 4 SECONDS AND S
2 FT AT 7 SECONDS.
TUE
N WINDS 15 TO 20 KT, BECOMING NW 5 TO 10 KT IN THE
AFTERNOON. SEAS 2 TO 4 FT. WAVE DETAIL: N 3 FT AT 5 SECONDS AND S
1 FOOT AT 7 SECONDS.
TUE NIGHT AND WED
S WINDS 10 TO 15 KT WITH GUSTS UP TO 20 KT.
SEAS 2 TO 4 FT. WAVE DETAIL: SW 3 FT AT 4 SECONDS AND E 2 FT AT
7 SECONDS.
WED NIGHT
SE WINDS 5 TO 10 KT, BECOMING NE AFTER MIDNIGHT.
SEAS 3 TO 4 FT. WAVE DETAIL: SW 3 FT AT 6 SECONDS AND E 3 FT AT
11 SECONDS.
THU THROUGH FRI NIGHT
E WINDS 10 TO 15 KT. SEAS 2 TO 3 FT.
SEAS ARE REPORTED AS SIGNIFICANT WAVE HEIGHT, WHICH IS THE
AVERAGE OF THE HIGHEST THIRD OF THE WAVES. INDIVIDUAL WAVE
HEIGHTS MAY BE MORE THAN TWICE THE SIGNIFICANT WAVE HEIGHT.
ANZ232-201800-
NANTUCKET SOUND-
104 AM EDT MON APR 20 2026
REST OF TONIGHT
NW WINDS 10 TO 15 KT WITH GUSTS UP TO 20 KT.
SEAS 2 TO 3 FT. WAVE DETAIL: NW 2 FT AT 4 SECONDS AND S 1 FOOT AT
6 SECONDS.
MON
W WINDS 5 TO 10 KT, BECOMING SW IN THE AFTERNOON. SEAS
AROUND 2 FT. WAVE DETAIL: W 1 FOOT AT 3 SECONDS AND S 1 FOOT AT
6 SECONDS.
MON NIGHT
NW WINDS 5 TO 10 KT, BECOMING N 10 TO 15 KT AFTER
MIDNIGHT. SEAS AROUND 2 FT. WAVE DETAIL: NW 2 FT AT 3 SECONDS AND
S 1 FOOT AT 6 SECONDS.
TUE
N WINDS 10 TO 15 KT, BECOMING NE 5 TO 10 KT IN THE
AFTERNOON. SEAS AROUND 2 FT. WAVE DETAIL: N 2 FT AT 5 SECONDS AND
S 1 FOOT AT 6 SECONDS.
TUE NIGHT AND WED
S WINDS 10 TO 15 KT WITH GUSTS UP TO 20 KT.
SEAS AROUND 2 FT. WAVE DETAIL: S 2 FT AT 3 SECONDS AND NW 1 FOOT
AT 4 SECONDS.
WED NIGHT
SE WINDS 5 TO 10 KT, BECOMING E AFTER MIDNIGHT. SEAS
AROUND 2 FT. WAVE DETAIL: SW 2 FT AT 5 SECONDS AND E 2 FT AT
9 SECONDS.
THU THROUGH FRI NIGHT
NE WINDS 5 TO 10 KT. SEAS AROUND 2 FT.
SEAS ARE REPORTED AS SIGNIFICANT WAVE HEIGHT, WHICH IS THE
AVERAGE OF THE HIGHEST THIRD OF THE WAVES. INDIVIDUAL WAVE
HEIGHTS MAY BE MORE THAN TWICE THE SIGNIFICANT WAVE HEIGHT.
ANZ233-201800-
VINEYARD SOUND-
104 AM EDT MON APR 20 2026
REST OF TONIGHT
NW WINDS 10 TO 15 KT WITH GUSTS UP TO 20 KT.
SEAS 2 TO 3 FT. WAVE DETAIL: SW 2 FT AT 6 SECONDS AND E 1 FOOT AT
7 SECONDS.
MON
W WINDS 5 TO 10 KT. SEAS AROUND 2 FT. WAVE DETAIL: SW 2 FT
AT 6 SECONDS AND E 1 FOOT AT 8 SECONDS.
MON NIGHT
NW WINDS 5 TO 10 KT, BECOMING N 10 TO 15 KT WITH
GUSTS UP TO 20 KT AFTER MIDNIGHT. SEAS AROUND 2 FT. WAVE DETAIL:
NE 2 FT AT 9 SECONDS AND W 1 FOOT AT 3 SECONDS.
TUE
N WINDS 10 TO 15 KT WITH GUSTS UP TO 20 KT, BECOMING E
5 TO 10 KT IN THE AFTERNOON. SEAS AROUND 2 FT IN THE MORNING,
THEN 1 FOOT OR LESS. WAVE DETAIL: N 2 FT AT 4 SECONDS AND S
1 FOOT AT 6 SECONDS, BECOMING N 1 FOOT AT 3 SECONDS AND S 1 FOOT
AT 6 SECONDS.
TUE NIGHT AND WED
S WINDS 10 TO 15 KT WITH GUSTS UP TO 20 KT.
SEAS 2 TO 3 FT. WAVE DETAIL: SW 2 FT AT 5 SECONDS AND E 1 FOOT AT
4 SECONDS.
WED NIGHT
SE WINDS 5 TO 10 KT, BECOMING NE AFTER MIDNIGHT.
SEAS 2 TO 3 FT. WAVE DETAIL: SW 2 FT AT 5 SECONDS AND SE 2 FT AT
12 SECONDS.
THU THROUGH FRI NIGHT
NE WINDS 5 TO 10 KT. SEAS AROUND 2 FT.
SEAS ARE REPORTED AS SIGNIFICANT WAVE HEIGHT, WHICH IS THE
AVERAGE OF THE HIGHEST THIRD OF THE WAVES. INDIVIDUAL WAVE
HEIGHTS MAY BE MORE THAN TWICE THE SIGNIFICANT WAVE HEIGHT.
ANZ234-201800-
BUZZARDS BAY-
104 AM EDT MON APR 20 2026
REST OF TONIGHT
W WINDS 10 TO 15 KT WITH GUSTS UP TO 20 KT.
SEAS AROUND 2 FT. WAVE DETAIL: W 2 FT AT 5 SECONDS AND E 1 FOOT
AT 7 SECONDS.
MON
W WINDS 5 TO 10 KT. SEAS AROUND 2 FT IN THE MORNING, THEN
1 FOOT OR LESS. WAVE DETAIL: W 1 FOOT AT 5 SECONDS AND E 1 FOOT
AT 8 SECONDS, BECOMING SW 1 FOOT AT 5 SECONDS AND E 1 FOOT AT
8 SECONDS.
MON NIGHT
NW WINDS 5 TO 10 KT, BECOMING N 10 TO 15 KT WITH
GUSTS UP TO 20 KT AFTER MIDNIGHT. SEAS 1 FOOT OR LESS, THEN
AROUND 2 FT AFTER MIDNIGHT. WAVE DETAIL: W 1 FOOT AT 3 SECONDS
AND S 1 FOOT AT 6 SECONDS, BECOMING N 2 FT AT 5 SECONDS AND S
1 FOOT AT 6 SECONDS.
TUE
N WINDS 10 TO 15 KT WITH GUSTS UP TO 20 KT, BECOMING E
5 TO 10 KT IN THE AFTERNOON. SEAS AROUND 2 FT IN THE MORNING,
THEN 1 FOOT OR LESS. WAVE DETAIL: N 2 FT AT 4 SECONDS AND S
1 FOOT AT 5 SECONDS, BECOMING N 1 FOOT AT 3 SECONDS AND S 1 FOOT
AT 6 SECONDS.
TUE NIGHT AND WED
S WINDS 10 TO 15 KT WITH GUSTS UP TO 20 KT.
SEAS AROUND 2 FT. WAVE DETAIL: SW 2 FT AT 3 SECONDS AND E 1 FOOT
AT 3 SECONDS.
WED NIGHT
SE WINDS 5 TO 10 KT, BECOMING NE AFTER MIDNIGHT.
SEAS AROUND 2 FT. WAVE DETAIL: SW 2 FT AT 5 SECONDS AND SE 2 FT
AT 13 SECONDS.
THU THROUGH FRI NIGHT
NE WINDS 5 TO 10 KT. SEAS AROUND 2 FT.
SEAS ARE REPORTED AS SIGNIFICANT WAVE HEIGHT, WHICH IS THE
AVERAGE OF THE HIGHEST THIRD OF THE WAVES. INDIVIDUAL WAVE
HEIGHTS MAY BE MORE THAN TWICE THE SIGNIFICANT WAVE HEIGHT.
ANZ235-201800-
RHODE ISLAND SOUND-
104 AM EDT MON APR 20 2026
REST OF TONIGHT
NW WINDS 10 TO 15 KT WITH GUSTS UP TO 20 KT.
SEAS 2 TO 3 FT. WAVE DETAIL: W 2 FT AT 4 SECONDS AND SE 2 FT AT
7 SECONDS.
MON
W WINDS 5 TO 10 KT. SEAS 2 TO 3 FT. WAVE DETAIL: SE 2 FT
AT 7 SECONDS AND W 1 FOOT AT 3 SECONDS.
MON NIGHT
NW WINDS 10 TO 15 KT, BECOMING N 15 TO 20 KT AFTER
MIDNIGHT. SEAS 2 TO 3 FT. WAVE DETAIL: NW 2 FT AT 3 SECONDS AND E
2 FT AT 7 SECONDS.
TUE
N WINDS 10 TO 15 KT WITH GUSTS UP TO 20 KT, BECOMING SE
5 TO 10 KT IN THE AFTERNOON. SEAS 2 TO 3 FT. WAVE DETAIL: N 2 FT
AT 3 SECONDS AND S 1 FOOT AT 7 SECONDS.
TUE NIGHT AND WED
S WINDS 10 TO 15 KT. SEAS 2 TO 3 FT. WAVE
DETAIL: SW 3 FT AT 4 SECONDS AND E 1 FOOT AT 6 SECONDS.
WED NIGHT
SE WINDS AROUND 10 KT, BECOMING NE AFTER MIDNIGHT.
SEAS 2 TO 3 FT. WAVE DETAIL: S 3 FT AT 6 SECONDS AND W 2 FT AT
3 SECONDS.
THU THROUGH FRI NIGHT
E WINDS 5 TO 10 KT. SEAS 2 TO 3 FT.
SEAS ARE REPORTED AS SIGNIFICANT WAVE HEIGHT, WHICH IS THE
AVERAGE OF THE HIGHEST THIRD OF THE WAVES. INDIVIDUAL WAVE
HEIGHTS MAY BE MORE THAN TWICE THE SIGNIFICANT WAVE HEIGHT.
ANZ237-201800-
BLOCK ISLAND SOUND-
104 AM EDT MON APR 20 2026
REST OF TONIGHT
NW WINDS 5 TO 10 KT WITH GUSTS UP TO 20 KT.
SEAS 2 TO 3 FT. WAVE DETAIL: W 2 FT AT 3 SECONDS AND SE 2 FT AT
7 SECONDS.
MON
W WINDS 5 TO 10 KT. SEAS AROUND 2 FT. WAVE DETAIL: SE 2 FT
AT 7 SECONDS AND W 1 FOOT AT 3 SECONDS. A CHANCE OF SHOWERS IN
THE AFTERNOON.
MON NIGHT
NW WINDS 5 TO 10 KT, BECOMING N 10 TO 15 KT WITH
GUSTS UP TO 20 KT AFTER MIDNIGHT. SEAS AROUND 2 FT. WAVE DETAIL:
NW 2 FT AT 3 SECONDS AND SE 2 FT AT 7 SECONDS.
TUE
N WINDS 10 TO 15 KT WITH GUSTS UP TO 20 KT, BECOMING S
5 TO 10 KT IN THE AFTERNOON. SEAS AROUND 2 FT. WAVE DETAIL: N
2 FT AT 4 SECONDS AND S 1 FOOT AT 7 SECONDS.
TUE NIGHT AND WED
S WINDS 10 TO 15 KT. SEAS 2 TO 3 FT. WAVE
DETAIL: S 2 FT AT 4 SECONDS.
WED NIGHT
E WINDS 5 TO 10 KT. SEAS 2 TO 3 FT. WAVE DETAIL: W
2 FT AT 3 SECONDS AND SE 2 FT AT 7 SECONDS.
THU THROUGH FRI
NW WINDS 5 TO 10 KT. SEAS 2 TO 3 FT.
FRI NIGHT
E WINDS 5 TO 10 KT. SEAS AROUND 2 FT. A CHANCE OF
SHOWERS.
SEAS ARE REPORTED AS SIGNIFICANT WAVE HEIGHT, WHICH IS THE
AVERAGE OF THE HIGHEST THIRD OF THE WAVES. INDIVIDUAL WAVE
HEIGHTS MAY BE MORE THAN TWICE THE SIGNIFICANT WAVE HEIGHT.
ANZ230-201800-
BOSTON HARBOR-
104 AM EDT MON APR 20 2026
REST OF TONIGHT
W WINDS 10 TO 15 KT. WAVES AROUND 2 FT.
MON
W WINDS 5 TO 10 KT. WAVES 1 FOOT OR LESS. A CHANCE OF
SHOWERS IN THE AFTERNOON.
MON NIGHT
NW WINDS 5 TO 10 KT, BECOMING N 10 TO 15 KT AFTER
MIDNIGHT. WAVES 1 FOOT OR LESS, THEN AROUND 2 FT AFTER MIDNIGHT.
TUE
N WINDS 10 TO 15 KT, BECOMING E 5 TO 10 KT IN THE
AFTERNOON. WAVES AROUND 2 FT IN THE MORNING, THEN 1 FOOT OR LESS.
TUE NIGHT AND WED
S WINDS AROUND 10 KT. WAVES AROUND 2 FT.
WED NIGHT
S WINDS 5 TO 10 KT, BECOMING SW AFTER MIDNIGHT.
WAVES 1 FOOT OR LESS.
THU THROUGH FRI NIGHT
NE WINDS 5 TO 10 KT. WAVES 1 FOOT OR
LESS.
SEAS ARE REPORTED AS SIGNIFICANT WAVE HEIGHT, WHICH IS THE
AVERAGE OF THE HIGHEST THIRD OF THE WAVES. INDIVIDUAL WAVE
HEIGHTS MAY BE MORE THAN TWICE THE SIGNIFICANT WAVE HEIGHT.
ANZ236-201800-
NARRAGANSETT BAY-
104 AM EDT MON APR 20 2026
REST OF TONIGHT
W WINDS 5 TO 10 KT. WAVES AROUND 2 FT.
MON
W WINDS 5 TO 10 KT. WAVES AROUND 2 FT. A CHANCE OF SHOWERS
IN THE AFTERNOON.
MON NIGHT
NW WINDS 5 TO 10 KT, BECOMING N 10 TO 15 KT AFTER
MIDNIGHT. WAVES AROUND 2 FT.
TUE
N WINDS 10 TO 15 KT, BECOMING S 5 TO 10 KT IN THE
AFTERNOON. WAVES AROUND 2 FT IN THE MORNING, THEN 1 FOOT OR LESS.
TUE NIGHT AND WED
S WINDS 10 TO 15 KT. WAVES AROUND 2 FT.
WED NIGHT
SE WINDS 5 TO 10 KT, BECOMING NE AFTER MIDNIGHT.
WAVES AROUND 2 FT.
THU THROUGH FRI
N WINDS 5 TO 10 KT. WAVES AROUND 2 FT.
FRI NIGHT
E WINDS 5 TO 10 KT. WAVES AROUND 2 FT. A CHANCE OF
SHOWERS.
SEAS ARE REPORTED AS SIGNIFICANT WAVE HEIGHT, WHICH IS THE
AVERAGE OF THE HIGHEST THIRD OF THE WAVES. INDIVIDUAL WAVE
HEIGHTS MAY BE MORE THAN TWICE THE SIGNIFICANT WAVE HEIGHT.
ANZ280-201800-
OCEAN WATERS FROM THE MERRIMACK RIVER TO PLYMOUTH FROM 40 TO
60 NM-
104 AM EDT MON APR 20 2026
REST OF TONIGHT
NW WINDS 15 TO 20 KT WITH GUSTS UP TO 25 KT.
SEAS 4 TO 5 FT. WAVE DETAIL: NW 4 FT AT 5 SECONDS AND SE 2 FT AT
7 SECONDS.
MON
W WINDS 10 TO 15 KT WITH GUSTS UP TO 20 KT, BECOMING SW
5 TO 10 KT IN THE AFTERNOON. SEAS 3 TO 5 FT, SUBSIDING TO 2 TO
3 FT IN THE AFTERNOON. WAVE DETAIL: W 3 FT AT 5 SECONDS AND SE
2 FT AT 7 SECONDS, BECOMING W 2 FT AT 4 SECONDS AND E 2 FT AT
8 SECONDS.
MON NIGHT
W WINDS 5 TO 10 KT, BECOMING N 10 TO 15 KT WITH
GUSTS UP TO 20 KT AFTER MIDNIGHT. SEAS 2 TO 4 FT. WAVE DETAIL: NE
4 FT AT 8 SECONDS AND NW 3 FT AT 4 SECONDS.
TUE
NE WINDS 10 TO 15 KT WITH GUSTS UP TO 20 KT, DIMINISHING
TO 5 TO 10 KT IN THE AFTERNOON. SEAS 2 TO 4 FT. WAVE DETAIL: N
4 FT AT 5 SECONDS AND S 1 FOOT AT 7 SECONDS.
TUE NIGHT THROUGH WED NIGHT
SW WINDS 10 TO 15 KT WITH GUSTS UP
TO 20 KT. SEAS 2 TO 3 FT. WAVE DETAIL: SW 3 FT AT 4 SECONDS AND E
3 FT AT 9 SECONDS.
THU THROUGH FRI NIGHT
N WINDS 10 TO 15 KT. SEAS 2 TO 3 FT.
WAVE DETAIL: NE 3 FT AT 7 SECONDS AND SW 2 FT AT 4 SECONDS.
SEAS ARE REPORTED AS SIGNIFICANT WAVE HEIGHT, WHICH IS THE
AVERAGE OF THE HIGHEST THIRD OF THE WAVES. INDIVIDUAL WAVE
HEIGHTS MAY BE MORE THAN TWICE THE SIGNIFICANT WAVE HEIGHT.
ANZ281-201800-
OCEAN WATERS FROM PROVINCETOWN TO NANTUCKET FROM 20 TO 60 NM-
104 AM EDT MON APR 20 2026
REST OF TONIGHT
NW WINDS 15 TO 20 KT WITH GUSTS UP TO 25 KT.
SEAS 4 TO 6 FT. WAVE DETAIL: NW 4 FT AT 5 SECONDS AND S 3 FT AT
6 SECONDS.
MON
NW WINDS 10 TO 15 KT WITH GUSTS UP TO 20 KT, BECOMING SW
5 TO 10 KT IN THE AFTERNOON. SEAS 3 TO 5 FT. WAVE DETAIL: NW 3 FT
AT 6 SECONDS AND SW 3 FT AT 7 SECONDS.
MON NIGHT
S WINDS AROUND 5 KT, BECOMING N 10 TO 15 KT WITH
GUSTS UP TO 20 KT AFTER MIDNIGHT. SEAS 3 TO 4 FT. WAVE DETAIL: NW
2 FT AT 5 SECONDS AND S 2 FT AT 7 SECONDS.
TUE
NE WINDS 10 TO 15 KT WITH GUSTS UP TO 20 KT, BECOMING N
5 TO 10 KT IN THE AFTERNOON. SEAS 3 TO 4 FT. WAVE DETAIL: N 3 FT
AT 6 SECONDS AND S 1 FOOT AT 7 SECONDS.
TUE NIGHT
N WINDS AROUND 5 KT, BECOMING SW AFTER MIDNIGHT.
SEAS 2 TO 3 FT. WAVE DETAIL: N 3 FT AT 6 SECONDS AND SW 1 FOOT AT
6 SECONDS.
WED
S WINDS 10 TO 15 KT. SEAS 2 TO 3 FT. WAVE DETAIL: E 3 FT
AT 10 SECONDS AND W 2 FT AT 3 SECONDS. A CHANCE OF SHOWERS IN THE
AFTERNOON.
WED NIGHT
SE WINDS AROUND 10 KT. SEAS 3 TO 4 FT.
THU THROUGH FRI NIGHT
N WINDS 10 TO 15 KT. SEAS 2 TO 4 FT.
SEAS ARE REPORTED AS SIGNIFICANT WAVE HEIGHT, WHICH IS THE
AVERAGE OF THE HIGHEST THIRD OF THE WAVES. INDIVIDUAL WAVE
HEIGHTS MAY BE MORE THAN TWICE THE SIGNIFICANT WAVE HEIGHT.
ANZ282-201800-
OCEAN WATERS FROM MARTHAS VINEYARD TO NANTUCKET FROM 25 TO 60 NM-
104 AM EDT MON APR 20 2026
REST OF TONIGHT
NW WINDS 15 TO 20 KT WITH GUSTS UP TO 25 KT.
SEAS 4 TO 6 FT. WAVE DETAIL: NW 5 FT AT 6 SECONDS AND E 3 FT AT
7 SECONDS.
MON
NW WINDS 5 TO 10 KT, BECOMING SW IN THE AFTERNOON. SEAS
3 TO 5 FT. WAVE DETAIL: W 4 FT AT 6 SECONDS AND S 2 FT AT
7 SECONDS.
MON NIGHT
W WINDS 5 TO 10 KT, BECOMING N 10 TO 15 KT WITH
GUSTS UP TO 20 KT AFTER MIDNIGHT. SEAS 3 TO 4 FT. WAVE DETAIL: W
2 FT AT 6 SECONDS AND E 2 FT AT 8 SECONDS. A CHANCE OF SHOWERS.
TUE
N WINDS 15 TO 20 KT, DIMINISHING TO 10 TO 15 KT IN THE
AFTERNOON. SEAS 3 TO 4 FT. WAVE DETAIL: W 3 FT AT 6 SECONDS AND
NE 3 FT AT 6 SECONDS.
TUE NIGHT
N WINDS 5 TO 10 KT, BECOMING SW AFTER MIDNIGHT. SEAS
2 TO 3 FT. WAVE DETAIL: E 3 FT AT 7 SECONDS AND W 1 FOOT AT
6 SECONDS.
WED
S WINDS 10 TO 15 KT. GUSTS UP TO 20 KT IN THE AFTERNOON.
SEAS 2 TO 4 FT. WAVE DETAIL: E 4 FT AT 10 SECONDS AND SW 3 FT AT
5 SECONDS. A CHANCE OF SHOWERS.
WED NIGHT
SE WINDS 10 TO 15 KT, BECOMING NE AFTER MIDNIGHT.
SEAS AROUND 4 FT.
THU THROUGH FRI
N WINDS 5 TO 10 KT. SEAS 2 TO 4 FT.
FRI NIGHT
NE WINDS AROUND 10 KT. SEAS 3 TO 5 FT.
SEAS ARE REPORTED AS SIGNIFICANT WAVE HEIGHT, WHICH IS THE
AVERAGE OF THE HIGHEST THIRD OF THE WAVES. INDIVIDUAL WAVE
HEIGHTS MAY BE MORE THAN TWICE THE SIGNIFICANT WAVE HEIGHT.
ANZ283-201800-
OCEAN WATERS FROM MONTAUK NY TO MARTHAS VINEYARD FROM 25 TO 60 NM-
104 AM EDT MON APR 20 2026
REST OF TONIGHT
NW WINDS 15 TO 20 KT. SEAS 4 TO 6 FT. WAVE
DETAIL: NW 5 FT AT 6 SECONDS AND S 2 FT AT 7 SECONDS.
MON
W WINDS 5 TO 10 KT. SEAS 3 TO 4 FT. WAVE DETAIL: W 3 FT AT
5 SECONDS AND S 2 FT AT 7 SECONDS.
MON NIGHT
NW WINDS 10 TO 15 KT, BECOMING N 15 TO 20 KT AFTER
MIDNIGHT. SEAS 3 TO 4 FT. WAVE DETAIL: NW 3 FT AT 4 SECONDS AND E
3 FT AT 8 SECONDS. A CHANCE OF SHOWERS IN THE EVENING.
TUE
N WINDS 15 TO 20 KT, DIMINISHING TO 10 TO 15 KT IN THE
AFTERNOON. SEAS 2 TO 4 FT. WAVE DETAIL: NW 4 FT AT 5 SECONDS AND
NE 4 FT AT 8 SECONDS.
TUE NIGHT
W WINDS 5 TO 10 KT, BECOMING SW 10 TO 15 KT AFTER
MIDNIGHT. SEAS 2 TO 3 FT. WAVE DETAIL: SW 2 FT AT 3 SECONDS AND
SW 2 FT AT 6 SECONDS.
WED
S WINDS 10 TO 15 KT WITH GUSTS UP TO 20 KT. SEAS 3 TO
4 FT. WAVE DETAIL: SW 4 FT AT 6 SECONDS AND E 3 FT AT 9 SECONDS.
A CHANCE OF SHOWERS.
WED NIGHT
SE WINDS AROUND 10 KT, BECOMING NE AFTER MIDNIGHT.
SEAS 3 TO 4 FT.
THU THROUGH FRI NIGHT
E WINDS 10 TO 15 KT. SEAS 2 TO 4 FT.
SEAS ARE REPORTED AS SIGNIFICANT WAVE HEIGHT, WHICH IS THE
AVERAGE OF THE HIGHEST THIRD OF THE WAVES. INDIVIDUAL WAVE
HEIGHTS MAY BE MORE THAN TWICE THE SIGNIFICANT WAVE HEIGHT.
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